Jim Gray wasn't very anxious for what he thinks is one of the cattle industry's best kept secrets to get out. But the Plains, TX, rancher knew it would only be a matter of time before news of a novel test for pregnancy determination in cattle using a simple blood test would become widespread.
To say he's sold on the blood pregnancy test system offered by Moscow, ID-based BioTracking LLC is an understatement.
“It works,” says Gray, owner of Holgate Land and Cattle. “In fact, it works so well I'm not sure I want everybody in the country to know about it.”
He's only kidding — sort of — in describing how the test fits his operation of buying other people's unwanted beef or dairy cows, putting “some pretty” on them, checking their pregnancy status, breeding them and reselling them as soon as possible as guaranteed bred cows.
Gray's secret is the BioPRYN™ test, which uses an enzyme-linked immunosorbent assay (ELISA) to evaluate bovine blood samples for pregnancy. It's simple, easy and inexpensive. The name of the test is an acronym for “Pregnant Ruminant Yes/No.”
“The beauty in the blood test is that you know you're not getting a ‘light-bred’ cow and calling her open,” Gray explains. “Especially in this market, the top end of bred cows — beef or dairy — are bringing such a premium that you can't take a chance on a wrong pregnancy diagnosis.”
He's careful not to sound like he's knocking the vets and technicians who preg-check by rectal palpation, though.
“I've got one of the best preg-checkers in the country,” he says, “and even the best can't find all those 30- to 60-day fetuses. Our experience is that this system finds virtually every one of them.”
For years, producers have been frustrated by the somewhat cumbersome nature of other pregnancy-detection methods, explains Garth Sasser, co-founder of BioTracking and developer of BioPRYN. “We're pleased to bring a new option that meets all of the criteria that beef or dairy producers want: It's fast, accurate, inexpensive, safe for the embryo and can detect pregnancy very early in gestation.”
How the test works
The testing technology was discovered by Sasser while he was a faculty/researcher at the University of Idaho, which licensed the technology to BioTracking. The test evaluates blood samples for the presence of a protein called pregnancy specific protein B (PSPB). This test, Sasser says, is unlike previous pregnancy tests that evaluated blood or milk for progesterone or other hormones or proteins that can occur in normally cycling animals. The only source of PSPB is the placenta.
BioPRYN can detect the presence of PSPB as early as 30 days after conception. Once producers have their samples collected, they send the blood to Moscow, ID, where it takes 27 hours to process the samples. Results typically are available the day after delivery to the lab.
Accuracy is an essential consideration for this type of technology. BioTracking claims that if the test detects cows open it is more than 99% correct; and if it detects cows pregnant it is 93-95% correct. Some of the false-positive results can be attributed to early embryonic death after a sample is collected rather than test inaccuracy.
“We really like the low incidence of false negatives because the open cows can be synchronized for breeding without worrying about aborting them if they actually are pregnant,” Gray says.
The test results are reported such that a rancher can also sort a herd depending on “how pregnant” a cow is at the time of sampling.
“We break the cows into trimesters,” Gray says. “That way, a rancher or dairyman can sort them into calving groups, or narrow up his calving window with his bought cows.”
Gray adds another advantage of the test is that it's not a “perishable” process. “If we're not in a rush, we can take blood samples over a week-long period, refrigerate them, and send them to the lab when we get the chance,” he says.
A cost-competitive test
At $1.95/test, the blood pregnancy diagnosis is comparable to the cost producers incur for veterinary palpation, and is less expensive than most ultrasound diagnoses. The test is especially cost-competitive for producers with small beef or dairy herds.
Bill Wallace, Conway, AR, is a cattle producer and production consultant for about 12 other cattlemen running a total of about 2,000 mother cows. He saw the BioPRYN test advertised a couple of years ago.
“Since then, I've tested about 2,000 samples from my own and clients' herds,” Wallace says. “We've been very happy with the blood test technique, and we haven't had an inaccurate result yet.”
Wallace, who also performs rectal palpation pregnancy tests, agrees it's a great system for smaller producers and for more intense operations. He says one of his seedstock clients was recently able to breed his heifers, take blood samples and get the test results back in time to rebreed the opens without setting them back more than one breeding cycle.
“And, it's easy enough that my 11-year-old grandson bled his own heifers and sent the samples in for analysis,” Wallace says.
He claims the blood test's biggest drawback is that a producer can't sort open cows from bred cows the same day as is possible with preg-checking by rectal palpation.
But, that's not normally a big concern for his clients, he says. “They're more interested in accuracy and convenience.”
Sasser says he's working on a chute-side testing protocol that would provide pregnancy results “in minutes.” That test may be available in a couple years.
Time and convenience
BioTracking also makes the test available to veterinary clinics. Ag Health Laboratories Inc. of Sunnyside, WA, was the first commercial animal clinic to offer the blood pregnancy test to clients. Co-owner Fred Muller, DVM, says the response has been tremendous.
“My dairy clients appreciate the fact they can identify open cows and return them to reproductive programs using tools like prostaglandins and/or other hormones,” Muller says. “They can gain at least a week compared to biweekly rectal palpation.”
Muller agrees with Gray and Wallace, who say the convenience of conducting the blood test on a producer's schedule, as opposed to working around a technician's or veterinarian's visit, is a valuable component of the test.
“Even if our lab wasn't performing the testing, I'd be in favor of my clients using it,” Muller says. “There are so many other management areas where we can concentrate our education and advice as veterinarians.”
And, in the big spread-out country of West Texas, Gray doesn't worry too much about putting the palpation technicians out of business.
“My son, who's palpated over 100,000 head of cows, was kind of insulted when we first started doing this blood test,” Gray says. “But he's all for it now. I think most of the time there are other things he'd rather be doing.”